I live in Shenzhen, and here in China you can pick up these Allwiner based tablets for about $100-$125 USD. My buddy couldn't resist a bargain and bought one a few weeks ago. I was surprised how well it worked out of the box. Decent performance browsing heavy pages, and the all the 3D games I could throw at it ran smoothly. That Allwiner blows the Rasberry’s CPU out of the water.
Initially, I was tempted to get one. Then I started noticing the problems. The accelerometer hadn't been properly calibrated or mounted at the factory, meaning some racing games you have to hold the device at a 20 degree angle to drive straight. When the battery started getting low, I plugged it in to its proprietary charger only to find out the touch screen doesn't work when charging.
Then about a week later my buddy said the screen popped out after he left it charging overnight. Turns out the battery had swollen up. All these issue point to shoddy cheap components and lack of testing and QC. With only $100 to spend, suggest a used Kindle or Nexus 7.